Functions of reducing agents (developers)... alkalis to permit the developing agent to reach all the silver salts... restrainers to make the developer selective... preservatives for long life of solutions... common developing solution troubles.
Features of fine-grain development... reasons for special problems in this field... of rates of development on gelatin and on silver grains... avoidance of alkalis... high content of formulas... two typical formulas... chemicals suitable for fine grain development.